How do I create and display the row and column of a hexagon grid

StephenRider

Hi,

I'm trying to figure out how to make display coordinates of each hexagon in a hex array. The numbers are a combination of the row and column of the hexagon. The following is an example of what I'm trying to do:

Thanks!

XanderBakker

Oh dear, mmm, I guess I did something wrong here... I used some code to create hexagons and analyzed the rows and columns to create the labels, but my hexagons are oriented differently... Oops. This is my result (I added the R and C to show what value represents the row and which one the column):

The code I used is:

import math
import arcpy
import os

# http://stackoverflow.com/questions/26691097/faster-way-to-calculate-hexagon-grid-coordinates
def calc_polygons_new(startx, starty, endx, endy, radius):
    sl = (2 * radius) * math.tan(math.pi / 6)

    # calculate coordinates of the hexagon points
    p = sl * 0.5
    b = sl * math.cos(math.radians(30))
    w = b * 2
    h = 2 * sl

    # offsets for moving along and up rows
    xoffset = b
    yoffset = 3 * p
    row = 1
    shifted_xs = []
    straight_xs = []
    shifted_ys = []
    straight_ys = []

    while startx < endx:
        xs = [startx, startx, startx + b, startx + w, startx + w, startx + b, startx]
        straight_xs.append(xs)
        shifted_xs.append([xoffset + x for x in xs])
        startx += w

    while starty < endy:
        ys = [starty + p, starty + (3 * p), starty + h, starty + (3 * p), starty + p, starty, starty + p]
        (straight_ys if row % 2 else shifted_ys).append(ys)
        starty += yoffset
        row += 1

    polygons = [zip(xs, ys) for xs in shifted_xs for ys in shifted_ys] + [zip(xs, ys) for xs in straight_xs for ys in straight_ys]
    return polygons

# create hexagons
result = calc_polygons_new(0, 0, 10, 10, 1)
cnt = 0
lst_x = []
lst_y = []
dct_hex = {}
for hexa in result:
    lst = []
    cnt += 1
    for tpl in hexa:
        pnt = arcpy.Point(tpl[0], tpl[1])
        lst.append(pnt)
    polygon = arcpy.Polygon(arcpy.Array(lst))
    x = polygon.labelPoint.X
    y = polygon.labelPoint.Y
    lst_x.append(x)
    lst_y.append(y)
    dct_hex[cnt] = [polygon, x, y]

# sort x and y label points lists
lst_x = sorted(list(set(lst_x)))
lst_y = sorted(list(set(lst_y)))

# create column number
col = 0
dct_x = {}
for x in lst_x:
    col += 1
    dct_x = col

# create row number
row = 0
dct_y = {}
for y in reversed(lst_y):
    row += 1
    dct_y = row

# define label
for cnt, lst in dct_hex.items():
    x = lst[1]
    y = lst[2]
    row = dct_y
    col = dct_x
    lbl = "C{0} R{1}".format("%02d" % (col,), "%02d" % (row,))
    lst.append(lbl)
    dct_hex[cnt] = lst

# create empty fc
arcpy.env.overwriteOutput = True
out_fc = r"C:\Forum\Hexagon\hexa03.shp"
path, name = os.path.split(out_fc)
arcpy.CreateFeatureclass_management(path, name, "POLYGON")

# insert hexagons
fld_lbl = "Label"
arcpy.AddField_management(out_fc, fld_lbl, "TEXT", None, None, 10)
flds = ("SHAPE@", fld_lbl)
with arcpy.da.InsertCursor(out_fc, flds) as curs:
    for cnt, lst in dct_hex.items():
        row = (lst[0], lst[3],)
        curs.insertRow(row)

I'm gonna dive into this again and generate the hexagons like you show in the image.

RTPL_AU_0-1762121688118.png